The company, a joint venture of AT&T and The Chernin Group, purchased a majority stake in Fullscreen in 2014.

Otter Media, the joint venture of AT&T and The Chernin Group, has assumed full ownership of two of its digital media properties, Fullscreen and Ellation.

"Marking a significant vote of confidence in its businesses, Otter has agreed to buy out all existing shareholders of each of Ellation and Fullscreen," a company spokeswoman said Wednesday in a statement. "Prior to this agreement, Otter owned more than 50% of each business."

Otter formed in 2014 to invest in and incubate digital businesses. The previous year, Chernin had purchased a majority stake in anime business Crunchyroll. Through Otter, Crunchyroll was rolled up into a digital subscription business, Ellation. Meanwhile, Otter acquired a majority stake in Fullscreen in 2014 in a deal that at the time valued the company between $200 million and $300 million. Existing investor WPP retained its stake in Fullscreen following the sale.

The fate of Otter has been largely up in the air as it awaits the sale of Time Warner to AT&T. At one time, it appeared that AT&T would acquire all of Otter once its $85 billion deal for Time Warner had closed, but the transaction has been held up by regulatory review.

Otter Media also owns a stake in Van Toffler's Gunpowder & Sky and has pacted with Reese Witherspoon on the launch of digital business Hello Sunshine.

CEO George Strompolos launched Fullscreen in 2011 as a YouTube network, known as an multi-channel network (MCN), that rolled up the audiences of online talent and packaged deals for advertisers. The company has evolved over the years, adding merchandise and touring businesses. It also briefly experimented with a subscription video business that shut down late last year.